America's poor are besieged by worms and parasites that are draining their health and energy, an expert said Tuesday.

And "diseases of neglect" associated with the developing world, such as dengue fever and Chagas disease, may become a bigger problem for the United States as the climate changes, said Dr. Peter Hotez of George Washington University and the Sabin Vaccine Institute in Washington.

"The message is a little tough because they are not killer diseases — they impact on child development, intellectual development, hearing and sometimes even heart disease," Hotez said in a telephone interview.

He said the diseases help to keep people mired in poverty, as infections may last years, decades or even lifetimes.

"Throughout the American South during the early twentieth century, malaria combined with hookworm infection and pellagra (a vitamin deficiency) to produce a generation of anemic, weak, and unproductive children and adults," Hotez wrote.

Hotez reviewed nine diseases affecting at least 10 million Americans for a report in the journal Public Library of Science Neglected Tropical Diseases, which he also edits.

"These diseases occur predominantly in people of color living in the Mississippi Delta and elsewhere in the American South, in disadvantaged urban areas, and in the U.S.-Mexico borderlands, as well as in certain immigrant populations and disadvantaged white populations living in Appalachia," he wrote.

Better sanitation, piped clean water, improvements in housing as well as better testing and medical treatment could help curb these "diseases of neglect," says the report.

(Agencies via Xinhua June 25, 2008)